Abstract：
:Wheelchair-dependent subjects often adopt a passive sitting posture and suffer from sitting acquired pressure ulcers (PU) that mainly occur when high buttock pressures sustain for a longer period of time. Body posture directly influences seating load and proper postural change is therefore essential. Many subjects cannot reposition themselves and seating systems that adjust sitting posture can regulate seating load and potentially diminish the risk to develop PU. We describe a mechanism for postural adjustments and investigated the influence of seat inclination (1), pelvis rotation (2) and chair recline (3) on buttock load. We developed an experimental simulator chair containing the concept to adjust body posture in the sagittal plane. Measurements involved quasi-static actuated chair movements in which chair configuration, buttock interface pressure and seating forces were simultaneously measured. Significant effects with high coefficients of determination (r(2)>0.8) were found for seating force, centre of pressure and sacral load. We conclude that a combination of independent pelvis rotation and seat inclination is effective to regulate the net buttock shear force and the sacral interface pressure in healthy subjects. Whether both techniques are also applicable in subjects without postural stability is still to be evaluated.
journal_name
J Biomechjournal_title
Journal of biomechanicsauthors
van Geffen P,Reenalda J,Veltink PH,Koopman BFdoi
10.1016/j.jbiomech.2008.04.012subject
Has Abstractpub_date
2008-07-19 00:00:00pages
2237-45issue
10eissn
0021-9290issn
1873-2380pii
S0021-9290(08)00200-5journal_volume
41pub_type
杂志文章abstract：:In this study the investigations made on about 50 trunk tissue densities are described. They were performed on ten cadavers of both sexes within 24 h of the moment of death. They were 20-40 yr old. The weight of each tissue was measured on a laboratory scale and the volume by placing the tissue in a pycnometer filled ...
journal_title：Journal of biomechanics
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更新日期：1990-01-01 00:00:00
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journal_title：Journal of biomechanics
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journal_title：Journal of biomechanics
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journal_title：Journal of biomechanics
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abstract：:The topographical distributions of the zonal properties of articular cartilage over the medial tibia from an experimental osteoarthritis (OA) model were evaluated as a function of external loading by microscopic Magnetic Resonance Imaging (µMRI). T2 relaxation times and cartilage thicknesses were measured at 17.6 µm r...
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journal_title：Journal of biomechanics
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journal_title：Journal of biomechanics
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doi：10.1016/j.jbiomech.2014.02.004
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journal_title：Journal of biomechanics
pub_type： 杂志文章
doi：10.1016/j.jbiomech.2012.08.047
更新日期：2013-01-04 00:00:00
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doi：10.1016/0021-9290(93)90352-f
更新日期：1993-11-01 00:00:00
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journal_title：Journal of biomechanics
pub_type： 杂志文章
doi：10.1016/j.jbiomech.2004.02.017
更新日期：2004-11-01 00:00:00
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journal_title：Journal of biomechanics
pub_type： 杂志文章
doi：10.1016/s0021-9290(00)00221-9
更新日期：2001-03-01 00:00:00
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journal_title：Journal of biomechanics
pub_type： 杂志文章
doi：10.1016/j.jbiomech.2009.07.040
更新日期：2010-01-19 00:00:00
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更新日期：1998-01-01 00:00:00
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journal_title：Journal of biomechanics
pub_type： 杂志文章
doi：10.1016/j.jbiomech.2015.02.034
更新日期：2015-06-01 00:00:00
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journal_title：Journal of biomechanics
pub_type： 杂志文章
doi：10.1016/s0021-9290(02)00227-0
更新日期：2002-12-01 00:00:00
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journal_title：Journal of biomechanics
pub_type： 杂志文章
doi：10.1016/j.jbiomech.2012.04.004
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journal_title：Journal of biomechanics
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journal_title：Journal of biomechanics
pub_type： 杂志文章
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pub_type： 杂志文章
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更新日期：2017-11-07 00:00:00
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pub_type： 杂志文章
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更新日期：2016-07-05 00:00:00
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更新日期：2016-02-29 00:00:00
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journal_title：Journal of biomechanics
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doi：10.1016/j.jbiomech.2004.07.028
更新日期：2005-08-01 00:00:00
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journal_title：Journal of biomechanics
pub_type： 杂志文章
doi：10.1016/j.jbiomech.2016.07.020
更新日期：2016-09-06 00:00:00
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journal_title：Journal of biomechanics
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更新日期：2009-09-18 00:00:00
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更新日期：2017-08-16 00:00:00
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journal_title：Journal of biomechanics
pub_type： 杂志文章
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更新日期：2010-01-19 00:00:00
abstract：:The six non-interacting modes for stress, strain and energy in an orthotropic elastic model of human femoral cortical bone tissue are discussed and illustrated. The stress and strain modes are illustrated using the representation of the stress and strain fields around a circular hole in a flat plate of cortical bone s...
journal_title：Journal of biomechanics
pub_type： 杂志文章
doi：10.1016/0021-9290(91)90311-a
更新日期：1991-01-01 00:00:00
